1. Field of the Invention
The present invention relates to an installation for the sterilization of medical products by irradiation.
2. Description of Related Art
It is known that tubes for extra-corporeal blood circulation, known as blood lines, which are used for extra-corporeal blood treatment, such as haemodialysis, undergo a sterilization process aimed at ensuring the complete elimination of germs. At the present time, this sterilization is carried out in various ways, for example by gamma-ray irradiation. However, this technique has various disadvantages linked to the dangerous nature of the material used for generating radiation, to the cost of shielding the irradiation equipment and to the difficulty in obtaining the official permits necessary for using it, in view of the growing awareness of environmental pollution. Moreover, high-temperature steam sterilization is unsuitable for PVC blood lines since, to ensure appropriate sterilization, it is necessary to employ a temperature near the softening point of PVC, thus entailing the risk of damage to the products.
At the present time, for further types of product, other irradiation methods are adopted, such as beta-ray irradiation, which do not cause the problems mentioned above. Beta-ray sterilization is, for example, used, with good results, for treating edible products or medical products of a non-critical nature.
However, where PVC blood lines are concerned, this sterilization treatment has not yet been used on a large scale due to the critical nature of the material and the stringent sterilization requirements demanded for such a use. In fact, on the one hand, the chemical and physical characteristics of PVC are extremely sensitive to irradiation doses and set strict upper limits to the doses which can be used and, on the other hand, the need for sufficient sterilization sets lower limits on these doses. Furthermore, irradiation installations which have not been designed specifically (such as third-party servicing installations) do not make it possible to ensure sufficient sterilization of the product as a whole, without some of the product being subjected to excessive exposure. In addition to this, the low unit price of the product makes it impossible to employ costly monitoring and management techniques if the competitiveness of blood lines sterilized by beta rays, as compared with lines sterilized by conventional methods, is to be maintained.